Effects of speed and incline on double-poling biomechanics

Abstract This study investigated the independent and combined effects of incline and speed on the kinetics and cycle characteristics of double poling. Seventeen trained male cross-country skiers completed a maximum speed, a maximum incline, and a constant-power-output test on a motorized treadmill. Axial pole force was measured throughout all tests using ski poles equipped with force sensors. The results indicated that the proportion of propulsive pole force relative to axial pole force (i.e., the pole force ratio) decreased linearly with increasing speed, which was explained by declining poling time. Contrarily, the pole force ratio and poling time barely changed by increasing incline; however, considerable inter-individual variation emerged in the former. A large proportion of variables describing cycle characteristics and poling kinetics differed significantly between the final completed stages of the maximum speed and maximum incline tests. Additionally, participants’ performance in these tests showed a moderate correlation ( $$r = 0.50$$ , $$P = 0.04$$ ). Both pole forces and poling impulse, as well as the pole force ratio, showed significant variation during the constant-power-output test, suggesting that, in cross-country skiing, external power output alone is insufficient to accurately capture the magnitude of effort, unless speed and inclination are also considered. The present study highlights the complexity of double-poling biomechanics and underscores the need for further research into physiology- and efficiency-related implications. Finally, it provides practical perspectives for enhancing sprint performance in cross-country skiing through targeted training sessions.